There are known semiconductor devices having power supply circuits which convert a power supply voltage into a desired voltage and output the voltage. Such power supply circuits are an inverter, a rectifier, a DC/DC converter and the like. Such semiconductor devices are used, for example, for a power conditioner of a solar power generation system, a server device, and the like. For the power supply circuit in the semiconductor device, a half bridge circuit or a full bridge circuit is used. Each of these circuits has a structure in which semiconductor switching elements are in cascade connection.
In order to enhance power conversion efficiency of such a power supply circuit, it has been being investigated in recent years that high electron mobility transistors (High Electron Mobility Transistors: HEMTs) using a GaN-based semiconductor material that enables operation at a high speed (for example, exceeding 100 MHz) (hereinafter, also referred simply as “GaN-HEMTs”) are applied to the switching elements.
Notably, Patent Literature 1 discloses an LED driving device using GaN-HEMTs.